Because pickup trucks, vans, station wagons, SUVs, and the like, are generally sold with fixed beds, conversion units are known in the art. Such conversion units, or auxiliary apparatus, is employed to provide means for the user to dump debris or to more easily load and unload articles. Generally, dumper auxiliary units are actuated by some power means, most frequently hydraulic pistons. Such units are expensive to install, largely incorporated into the structure of the truck bed and therefore substantially fixed and permanent, prone to breakage and expensive to maintain, and slow in operation. Notably, because of their fixed installation, they tend to reduce the flexibility in vehicle uses and all but eliminate the owner's motivation to swap accessories according to need or predilection, e.g., to change the dumper for a camper shell.
Illustrative and exemplary known prior art devices include the dumper shown in U.S. Pat. No. 6,371,564 to Yates et al, which teaches a system for dumping material from a dump box in a pickup truck where the dump box first rolls slightly to the rear so as to clear a bumper or other structure on the rear of the vehicle. Then the dump box lifts via hydraulic side mounted pistons.
U.S. Pat. No. 6,196,634 B1, to Jurinek, discloses a movable bed liner hinged at the back end for converting a pickup truck into a dump truck. A pair of linear hydraulic rams disposed in respective compartments in front of the wheel wells is operable to raise and lower the dump body liner. The invention purportedly uses otherwise unusable, “dead” space in front of the wheel wells and preserves the appearance of a normal flatbed pickup truck.
U.S. Pat. No. 5,267,779, to Talamantez, Jr. et al, teaches a pickup truck conversion dumping body having two separate assemblies; one comprising an open cargo box configured to accommodate pickup truck cargo bed; and a companion assembly comprising a track system with a movable carriage which may be maneuvered back and forth with a chain drive. The two assemblies are attached to one another with the cargo box body riding upon the carriage and attached to the carriage with connecting links. The carriage is arranged into the track system with casters so that it can ride in a horizontal position under normal operation. An escape pattern is provided with the track system, which allows the cargo box to be easily tilted. When the carriage has traveled a predetermined distance, the cargo box is then tilted downward by the force of gravity, causing its contents to be dumped. When the cargo box body is not needed for dumping purposes it may be disconnected from carriage.
U.S. Pat. No. 4,681,371, to Leonard, discloses a dumper comprising a framework, a tiltable bin, a pair of latches, rollers, a pair of hooks, a rod, and a pair of handles. The framework comprises a pair of longitudinal tracks with one long arm located orthogonally to and coplanarly with the longitudinal tracks; and two shorter arms and, parallel to the long arm. The long arm is mounted at the rear end of the truck bed, while the two shorter arms are mounted at the middle and front end of the tracks, respectively. The framework is removably secured to the truck bed. The tiltable bin is slidingly mounted on the framework. The bin pivots through the use of two hooks and a hook stop or rod. The hooks are mounted on the underside of the bin, in the inner space between the two parallel tracks, and are equally spaced to the tracks. The hooks are located near the center of gravity of the bin and toward the front end of the bin. The hook stop or rod is mounted at the rear end of the longitudinal tracks and spans between the tracks.
U.S. Pat. No. 3,915,496, to Mabry Jr., shows a dumping device comprising a unit adapted for placement in a pickup truck. The unit includes a cargo box that moves longitudinally along a set of rollers and a jack for tilting the box.
The foregoing patents reflect the current state of the art of which the present inventor is aware. Reference to, and discussion of, these patents is intended to aid in discharging Applicant's acknowledged duty of candor in disclosing information that may be relevant to the examination of claims to the present invention. However, it is respectfully submitted that none of the above-indicated patents disclose, teach, suggest, show, or otherwise render obvious, either singly or when considered in combination, the invention described and claimed herein.